"Welcome to the secretive world of golf ball retrieval". Typically, a retriever pays a golf course 5-10 cents per found ball for the exclusive rights to collect balls on their property. The retriever profiled in the story collects around 1,000 to 3,000 balls a day or 150,000 to 300,000 per year. After he cleans them, "he can resell them for anywhere between thirty cents for a dud range ball to two bucks for the gold-standard Titleist Pro V1x". As the article says, "You do the math..." (Via Obscure Store.)